I'm trying to isolate x to find range, but unsure how to manipulate equation.

Thread starter My8th
Start date Apr 21, 2012
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Range

AI Thread Summary

To find the range of the function y = 8x^2 + 8x + 5, the equation can be rearranged to y - 5 = 8x^2 + 8x. By isolating y, the next step involves solving the quadratic equation 8x^2 + 8x + (5 - y) = 0. The discussion highlights the challenge of factoring the x^2 + x component. Participants suggest manipulating the equation further to isolate x and determine the range effectively. Understanding the properties of quadratic functions will aid in finding the range.

Apr 21, 2012

My8th

Homework Statement

Find Range

Homework Equations

y=8x^2+8x+5

The Attempt at a Solution

y-5=8x^2+8x Subtracted five both sides

(y-1)/8=(x+1)x divided 8 to both sides, and factored x out.

The x^2+x part has me stumped.

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Apr 21, 2012

tiny-tim

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solve 8x² + 8x + 5 - y = 0

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